Add 12/90 and 21/18
1st number: 12/90, 2nd number: 1 3/18
12/90 + 21/18 is 13/10.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 90 and 18 is 90
Next, find the equivalent fraction of both fractional numbers with denominator 90 - For the 1st fraction, since 90 × 1 = 90,
12/90 = 12 × 1/90 × 1 = 12/90 - Likewise, for the 2nd fraction, since 18 × 5 = 90,
21/18 = 21 × 5/18 × 5 = 105/90 - Add the two like fractions:
12/90 + 105/90 = 12 + 105/90 = 117/90 - 117/90 simplified gives 13/10
- So, 12/90 + 21/18 = 13/10
In mixed form: 13/10
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